Despite oft-touted fears of a hard landing, for the last five years the story told by official GDP figures has been felicitously dull. China grew by 6.7 percent year-on-year for three quarters in a row in 2016, squarely within the government's goal of a 6.5 percent to 7 percent expansion.

But those statistics mask the drivers of growth in the world's second-largest economy, argue Bank of America Merrill Lynch economists Helen Qiao and Sylvia Sheng. A gauge compiled by the bank suggests the nation has had a much more volatile ride, and risks a slowdown in investment demand next year without further stimulus.

"If you look at GDP only, then you would think the Chinese economy is going so smoothly, very much muddling through the doldrums," said Qiao, chief Greater China economist and head of Asia ex-Japan economics research, in a media briefing on Thursday. According to the BofAML China-Aggregate Coincident Tracker, there have been several policy-induced mini-cycles over the last five years that suggest a much less stable path than that visible in headline figures.

Source: Bank of America Merrill Lynch

Just after the trough of the 2015 mini-cycle, the government boosted spending to shore up growth amid a manufacturing and property slowdown. They also cut taxes on passenger-vehicle purchases by half, to 5 percent, and rolled out easing measures for the property sector by lowering mortgage-deposit requirements and slashing minimum down payments.

Source: Bank of America Merrill Lynch

The effect of that stimulus was immediate. Now, "policy makers are largely of the belief that the Chinese economy is doing fairly well and that growth momentum is resilient," said Qiao. That may mean there is "little incentive" for further easing measures.

She termed the latest stage of the mini cycle the "the complacency phase." Without fresh stimulus, Qiao and Sheng anticipate no pick-up in growth next year, with a 6.6 percent pace expected versus 6.7 percent this year.

"Hopefully with more foresight into a potential slowdown led by weaker investment demand, policy makers could adopt counter-cyclical policy adjustments in time to smooth the cycle," concludes Qiao.